Magnetic seal clamp



June 26, 1956 w. E. ERICKSON 2,752,030

MAGNETIC SEAL. CLAMP Filed Feb. 8. 1954 2 Sheets-Sheet 1 FIG. I.

INVENTOR. WARREN E. ERICKSON falm 214% June 26, 1956 w. E. ERICKSON MAGNETIC SEAL. CLAMP 2 Sheets-g 2 Filed Feb. 8' 1954 FIG.

WARREN E. ERICKS United States Patent MAGNETIC SEAL CLAW Warren E. Erickson, Madison, Wis., assignor to Gisholt Machine Company, Madison, Wis., a corporation of Wisconsin Application February 8, 1954, Serial No. 408,758

10 Claims. (Cl. 198-211) This invention relates to a magnetic seal clamp for use in machines adapted to apply tubular seals to bottle tops and the like.

In such machines the seals are first stripped in succession from one or more magazines and speared to partially open them, and transferred to suitable heads for further opening and final application to the individual bottle tops. The stripping is generally accomplished by vacuum means which present the seals in succession to a pick-off station where a spear carried by a rotating arm is made to enter the seal and a clamp secures the seal upon the spear as the spear dwells at the pick-off station; after which the seal is released from the vacuum and the spear arm resumes its rotary movement.

Heretofore, the clamping of the seal to the spear has been accomplished by complicated mechanism including a spring biased lever on the arm which was actuated by an oscillating cam driven in correlation to the drive of the rotary spear arm whereby the clamp was opened by the cam as the spear approached and entered the seal, and again as the seal reached the transfer station for pickup by a head. Suitable apparatus of this type is illustrated in the copending application of William Barton Eddison, Serial No. 407,846 filed February 3, 1954, and assigned to the assignee of the present application.

The present invention greatly simplifies the clamp construction and operation and provides a clamp which is independent of wear in both open and closed positions.

According to the invention the clamp comprises a pivotal lever arm held in both closed and open positions by a permanent magnet core thereon coacting with a corresponding armature in each position, and a cam is positioned to shift the lever from one position to the other in correlation to the movement of the rotary arm carrying the spear.

The accompanying drawings illustrate the best mode contemplated for carrying out the invention.

In the drawings:

Figure 1 is a face view of the spear wheel and the stripper and transfer mechanism in part;

Fig. 2 is a side elevation of the spear wheel and adjacent parts partly in section;

Fig. 3 is a detail section of the cam taken on line 33 of Fig. 2;

Fig. 4 is an enlarged detail side elevation showing the clamp open as the spear approaches the pick-off station and is entering a seal as shown by the dash lines in Figure 1; and

Fig. 5 is a view similar to Fig. 4 taken on line 5-5 of Figure 1 showing the clamp closed upon the seal after the latter has been fully speared.

In the apparatus illustrated which in general constitutes the subject matter of a copending application of the present inventor jointly with William Barton Eddison, Serial No. 416,184, filed March 15, 1954, the seals 1 are contained in a pair of magazines 2 and are stripped alternately therefrom by a stripper disc 3 to a pick-off station 4 Where they are individually speared and taken to a transfer station 5 to be picked up by a two-finger transfer head 6.

The spearing of the individual seals at the pick-01f station 4 is effected by a rotary spider 7 having four generally radial arms 8 each carrying a spear 9 secured thereto at its outer end.

Each spear 9 extends tangential to the circumferential path of travel of its point as the spider 7 rotates, and extends forwardly in the direction of travel from its corresponding supporting arm 8 a distance sufiicient to receive a seal and permit clamping of the seal thereon. Each spear 9 is secured to the backside of the corresponding arm 8 leaving the space adjacent to the spear, i. e. both radially inward and radially outward therefrom, free for the passage of the two spaced fingers 10 of the transfer head 6 as the latter picks up a seal from the spear.

The seal 1 is clamped upon spear 9 by means of a clamp lever 11 pivoted upon a pin 12 protruding from the side of the corresponding arm 8 in the direction of rotation for spider 7. The lever 11 extends generally parallel to arm 8 and carries at its outer end a permanent magnet 13 which serves as the clamp by pressing one flat side of the seal against the side of the corresponding spear 9. The spear 9 is made from magnetically permeable stainless steel to be free from corrosion from the seals.

The magnet piece 13 is shown as comprising a replaceable cylindrical member secured in a circular opening in the split free end of lever 11 by means of a bolt 14 which tightens the parts of the lever end thereon and holds the magnet piece with its inner end protruding toward the spear 9.

Actuation of the clamp is obtained by moving lever 11 from an open clamp position wherein the outer end of magnet piece 13 is magnetically secured to a stop 15 on the front of arm 8, to a closed clamp position wherein the inner end of magnet piece 13 is held magnectically to the spear 9 with one wall of the seal 1 therebetween.

The lever 11 is moved from the open clamp position to the closed clamp position after the spear 9 fully enters a seal 1 and while dwelling at the pick-off station 4. For this purpose a push rod 16 extending through the machine housing 17 back of spider 7 is adapted to engage an adjustable screw end 18 on the short inner end of clamp lever 11 as arm 8 reaches the station 4 to pick the seal off from stripper disc 3. Push rod 16 is actuated by a cam sleeve 19 on the continuously rotated shaft 20 which carries the spider 21 on which heads 6 are mounted. The push rod 16 is normally retracted against sleeve 19 by a coil spring 22 disposed thereonbetween housing 17 and a collar 23 on the rod.

The magnet piece 13 continues to clamp the seal 1 upon spear 9 as the spider rotates until the seal reaches the transfer station 5 where the rotation of the spider slows up or dwells and the fingers 10 of head 6 travel into the seal above and below the spear 9.

Just as the fingers 10 complete their entry into the seal clamp lever 11 is pushed to open clamp position by means of a cam plate 24 on head 6 which engages an adjustable screw end 25 on lever 11 to push the latter outwardly to break the clamping magnetic pull and carry magnet piece 13 to stop 15 whereby the clamp is held open, whereupon continued rotation of head 6 past the transfer station 5 causes fingers 10 to pick the seal 1 from the spear 9.

The clamp then continues open as spider 7 rotates until the corresponding spear 9 enters another seal at the pick-off station 4.

The invention provides a clamp which never misses in action regardless, and in which the clamping forces are always constant and generally independent of mechanical wear and structural complications. 7

Various embodiments of the invention may be em ployed within the scope of the following claims which particularlypoint out and distinctly claim the subject matter regarded as the invention.

I claim: a l. in a machine of the class described for placing tubular seals on bottle tops and the like, a rotary'member carrying a spear at its circumference adapted to spear a seal at a pick-oft station and to carrythe seal to a transfer station where it is picked up from the spear by a transfer head, and a magnet clamp carried by' said member and adapted to clamp the seal uponthe spear.

' 2. The construction of claim 1 in which the clamp comprises a lever pivoted to the rotary member and carrying a permanent magnet at i-tsfree end, the pivotal movement of said lever freely carrying the magnet between closed and open clamp positions, the closed clamp position being maintained by magnetic attraction of the magnet to the spear with a Wall of the seal therebetween andthe open clamp position being maintained by magnetic attraction of the magnet to a stop piece carried by the rotary member.

3. In a machine of the class described for placing tubular seals on bottle tops and the like, a rotary member carrying a spear at its circumference adapted to spear a seal at a pick-off station and to carry the seal to a transfer station where it is picked up from the spear by a transfer head, a clamp lever pivoted to said' member, a magnet piece carried by said lever and serving to hold the same in either open or closed clamp position, and means to actuate said lever from one position to the other in correlation to the movement of said member.

4. In a machine of the class described for placing tubular seals on bottle tops and the like, a rotary member carrying a spear at its circumference adapted to spear a seal at a pick-off station and to carry the seal to a transfer station Where it is picked up from the'spear by a transfer head, a clamp lever pivoted to said' member, a magnet piece carried by said lever and serving to hold thesame in either open or closed clamp position, and means to actuate said lever to close the clamp upon spearing of a seal at said pick-elf station.

5. The construction of claim 4 in which said last named means comprises a cam disposed to actuate said lever upon said member reaching a predetermined posiby a transfer head, aclarnp, lever pivoted to said member, 7

a magnet piece carried by said lever 'and serving to hold h same in eit er ope or closed clamp Posi ion, and means to actuate said, lever to open the: clamp at said transfer station.

7. The construction of claim. 6 in which said last named means comprises a movable cam adapted to engage said lever at said transfer statiom 8. In a machine of the class described for placing tubular seals on bottle tops and the like, a rotary member carrying a spear at its circumference adapted to spear a seal at a pickeoif' station and to carry the seal to a transfer station where it is picked up from the spear by a transfer head, a clamp lever pivoted to said member, a magnet piece carried by said lever and serving to hold the. same in either open or closed clamp position, means to actuate said lever to close the clamp upon spearing of a seal at said pick-01f station, and means to. actuate said lever toopcn the clamp at said transfer station to provide for stripping of the seal from the spear.

9. The construction of claim 8 in which said first named means comprises a cam disposed to actuate said lever upon said member reaching a predetermined posi References Cited in the file of this. patent UNITED STATES PATENTS.

Phelps May ll, 1915 Nordquist Aug. 17, 1943 

